AT PASSOVER, JEWS WORRY AND DEBATE ABOUT VANISHING INTO AMERICA

As millions of Jewish families hold Passover Seders this week, in many households the ritual celebration of deliverance from Egypt will be followed by talk of a new predicament. Prompted partly by a debate between two pugnacious lawyer-authors--and partly by dire statistics, which, over years, have become as rote as the Passover Haggadah--a generation will look at its children and speculate whether its grandchildren will be Jews at all.

Alan Dershowitz's book, The Vanishing American Jew (Little, Brown; 395 pages; $24.95), has been out only a month, but its title describes a crisis long under way. For decades, while their opportunities...